For the purposes of this application, the term “plumbing” shall refer to piping systems used to convey liquids and gases in both residential and commercial environments. The term “coupling” or “coupler” shall refer to any fitting, including but not limited to reducers, collars, sleeves and unions used to connect sections of piping. The terms “pipes” or “piping” shall also include tubing, ducting and conduit.
Couplings are commonly used to temporarily or permanently connect piping sections in plumbing applications. If the coupling is not centered properly between the ends of these sections, leaking may occur. Ordinarily, two pipes of equivalent diameter are connected to make one longer section of pipe; however, pipes of varying diameters may also be joined using a reducer style coupling.
Each coupling will have an inner diameter equal to or slightly larger than the corresponding exterior diameters of the pipes being joined. During installation, a coupling having a wall or annular thickness (hereinafter referred to as the annulus) is placed over an open end of one of the pipes. The two piping sections are then placed end-to end such that they are substantially aligned along their longitudinal axes, and the coupling is advanced along that longitudinal axis. When a coupling is properly installed, it is positioned such that it is substantially centered over the ends of the two pipes being joined within it (hereinafter referred to as the seam.) It should be recognized that in the case of reducers, the coupling will be placed on the pipe having the smaller of the two diameters before it is driven into place over the larger diameter pipe. Once again, the installer will advance the coupler until it is substantially centered on the pipe seam.
Oftentimes the tolerance between the inner diameter of the coupling and the outer diameter of the pipe is very tight, making it difficult to position the fitting between the pipe seam. Burrs on the pipe exterior and coupling interior can also inhibit movement of the fitting. It is especially important to properly align couplings in electrofusion applications. Electrofusion couplings are fitted with resistive elements; when a specific voltage is applied to these elements, the integrated heater coils melt both the interior of the fitting and exterior of the pipes. If the coupling is not properly centered about the pipe seam, the joint may leak or may fail prematurely.
Manufacturers typically recommend placing a wooden block on the edge of the fitting 25 and striking that block with a hammer to advance the coupling into position. See e.g. page 13, Section 8 of the “Central Electrofusion Installation Manual” https://www.hdpe.ca/wp-content/uploads/2016/03/GFCP-EF-Installation-Booklet.pdf.Oftentimes the block will force the coupling to skew as it advances and the installer must then hit another area of the coupling to correct the angle of the coupling. Consequently, this method requires frequent repositioning of the block about the circumference of the fitting and often requires the installer to hit the block outside of his line of sight. This practice is damaging to the fitting and may affect the integrity of the connection between the pipes and coupling. In addition, this approach poses a safety hazard as the wood may splinter or slip and requires the installer to spend unnecessary time squaring the coupler.
There is therefore a need in the art for a tool that can be used to drive a coupling into proper position in a manner that minimizes or eliminates damage to the plumbing components.